Safety



(No Model.)

B. A. GHESEBRO-UGH.

SAFETY APPLIANCE FOR ELEVATORS.

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Patented July 1, 1884.,

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ROBERT A. OHESEBROUGH, OF NEWV YORK, N. Y.

SAFETY APPLIANCE FOR ELEVATORS.

SPECIFICATION forming part of Letters Patent No. 301,213, dated July 1,1884:.

Application filed April 8, 1884. (No model.)

To all whom it mpg concern.-

Be it known that 1, ROBERT A. Grrnsn BROUGH, of the city and county ofNew York, in the State of New York, have invented a new and usefulImprovement in Safety Appliances for Elevators, of which the followingis a specification.

My invention relates to the class of appliances for elevators which aredesigned to check or retard the fall of the elevator car, cab, or

platform when the hoisting-rope breaks or any other accident occurswhich would allowthe oar, cab, or platform to fall were it not for suchappliances.

In my United States Letters Patent No. 286,684, dated October 16, 1883,I have shown and described in connection with an elevatorshaft and acar, cab, or platform working therein a cylinder fixed at the bottom ofthe shaft, and a piston or plunger fitting therein and attached to thebottom of the car, cab, or platform in such a manner that the rise andfall of the car, cab, or platform will cause a reciprocating movement ofthe piston or plunger in the cylinder, and a vent-aperture through whichair or other elastic fluid may enter and leave the cylinder, thecylinder being of such length that the piston or plunger remains thereinduring the whole travel of the car, cab, or platform, and the wholebeing independent of the mechanism for raising and lowering the car,cab, or platform, and forming a safety appliance for retarding the fallof the ear, cab, or platform.

My present invention consists, essentially, in the combination, with anelevator-shaft and a car, cab, or platform working therein, of acylinder fixed at the bottom of the shaft and adapted to receive andcontain a liquidsuch as water or oil-and a piston or plunger attached toand working with the car, cab, or platform, and'constructed to form apassage to allow liquid to pass downward below it as it ascends, thewhole forming a safety appliance independent of the mechanism employedto operate the car or cab. A solid piston loosely fitting in thecylinder, so as to leave an annular space or passage between thecylinder and piston and for the passage of water, could be used wherethe resistance offered to the upward movement of the piston would not bean obstacle; but in case it is desired that the piston should movefreely upward the piston should be formed with openings or passages andfitted with a valve to open as the piston rises and close as itdescends. Such a safety appliance applied to an elevator will preventthe car, cab, or platform from ever descending at too great a speed,even though the hoistingrope should not break, and hence forms a verydesirable addition to an elevator.

In the accompanying drawings, Figure 1 represents a vertical section ofmy safety appliance employed in, connection with an elevator-shaft andcar or cab, the car or cab being at the top of the shaft, and thepiston-rod being steadied and stayed by a single brace.

Fig. 2 is a sectional View corresponding to Fig. 1, the ear or cab beingnear to its lowest position, and portions of the figure being brokenaway to reduce the height thereof. Fig. 3 is a sectional elevationcorresponding to Fig. 1, with two braces for the piston-rod. Fig. 4: isa horizontal section showing the corner-posts of the elevator-shaft anda plan of one of the braces; and Figs. 5 andG respectively represent apiston as descending and ascending in a cylinder, and upon a largescale.

Similar letters of reference designate corresponding parts in all thefigures.

A designates the shaft, and B the car, cab, or platform, arranged totravel therein, it being guided in any wellknown manner upon thecorner-posts a. I have here represented the shaft A as four floors, G,in height; but obviously the number, of floors in buildings in which areelevators will vary greatly.

D designates the hoisting-rope, attached to the top of the car or cab B,and passing'around or over sheaves or pulleys b. I have not representedany hoisting mechanism, as it forms no part'of my invention; but thatemployed may be of any suitable character.

E designates a tube or cylinder sunk in the earth at the bottom of theshaft A, and composed of cast or wrought iron, as may be most desirable.In this cylinder is a piston or plungcr, F, which can move freelytherein, and which is attached by a rod, F, to the car or cab A.

The piston or plunger F is best shownin Figs. 5 and 6', and there itwill be seen that it through it.

is valvular, or has openings or passages c As here shown, the piston isscrewed upon the rod F, and upon the lower piston will move freelyupward because of the space afforded by the openings 0 and by the spacearound the piston for the passage of liquid downward. "When the cardescends, the valve d closes, as shown in Fig. 5, and as the liquid canonly pass upward around the piston the descent ofthe latter and the caror cab will be greatly retarded. It is therefore not desirable that thepiston should work tightly in the cylinder, and hence no packing for thepiston is necessary.

The rod F may be of metal or wood, and, if of metal, will preferably behollow or tubular, to give it increased stiffness, with less metal thanin a solid rod. VVhenthe rod F is of considerable length, there might beliability of its bending or buckling and breaking when a loaded car issupported upon it, and to the end that it shall not be liable to suchaccident I employ braces G, which consist of arms radiating from a hubor sleeve, 0, fitting loosely the rod F, and through which said rod mayslide, the arms being guided in any suitable manner by the posts a.

In Figs. 1 and 2 I have shown only a single brace, G, connected bychains or other connections,], with the car B; but in Fig. 3 I haveshown a second brace, G, suspended by chains or connections 1'' from thefirst brace, G. \Vhen the car or cab descends, these braces deposit atthe bottom of the shaft; but in ascending the car or cab picks up firstthe brace G, and then the brace G, and so sustains the rod F. In orderthat the chains ff, as they are deposited on the braces as the cardescends, may

' not drop down through and become entangled,

each brace preferably supports a grating, screen, or other floor, 9, asshown in Fig; 4, on which the chain is laid or deposited.

Obviously, if the cylinder E is filled with liquid, as shown in Fig. 1,when the piston is at the top of its stroke, that volume of water cannotbe held by the cylinder when the piston is at the bottom of thecylinder, owing to the displacement of the rod F. If the rod be hollow,liquid may be admitted to it as the piston descends, so as to reduce thedisplacement; but even this would or might not be sufficient. In orderto obviate this difficulty, I connect with the upper end of the cylinder'E by a pipe, h, a reservoir, h, and when the piston descends the liquiddisplaced from the cylinder will pass into the reservoir which is shownin Figs. 1 and 3.

In lieu of employing chains for raising the brace or braces G, I mayemploy a. pistonrod having collars which act upon the braces to raisethem on coming against the under side thereof; or, in lieu of a rodhaving collars, a rod having portions of different diameter forming ashoulder or shoulders might be employed. In either case the hole in thetop of the cylinder should be large enough to permit, the passage of thecollars or shoulders.

The advantage resulting from the use of the valve d is that the pistoncan then move upward freely as the car or cab rises; but in some casesthe piston might be made solid and without a valve, and if fittedloosely in the I resistance to the upward movement of the car or cab ata normal spee we I am aware that a cylinder and piston or plunger placedbelow an elevatorcar, cab, or platform have been employed as a means ofraising and lowering the same, and I make no claim to such an apparatusas of my invention. In such an apparatus-the water or other fluid isforced into the cylinder under pressure to raise the elevator car, cab,or platform, and all parts of the apparatus must be of very fineconstruction to be absolutely watertight, so that when water is forcedin below the piston the latter and the superposed car or cab will beelevated. In my apparatus there is no necessity of a tightly-fittingpiston, and the apparatus is not and cannot be employed to raise the caror cab, but forms a safety appliance entirely independent of themechanism for that purpose. In my apparatus the water or liquid remainsa constant quantity in the cylinder, and when the car or cab is hoistedit draws up the piston, and the liquid above passes down around theloosely-fitting piston and through the downwardly-opening valve, if thepiston is provided with a'v'alve.

What I claim as my-invention, and desire to secure by Letters Patent,is- 1. The combination, with an. elevator-shaft and a car, cab, orplatform working therein, of a liquid-cylinder at the bottom of saidshaft and a piston or plunger attached to and moving with the car orcab, and constructed to form a passage to allow liquid to pass downwardbelow it as it ascends, the whole forming a safety appliance independentof the mechanism employed to operate the car or cab, substantially asherein described.

2. The combination, with an elevator-shaft and a car, cab, or platformworking therein, of a liquid-cylinder at the bottom of the shaft, avalvular piston or plunger attached to and moving with said can or cab,and a valve applied to said piston or plunger, and serving to permit afree passage of the piston or plunger upward through the liquid in thecylinder,

and to retard its downward movement by the i). The combination, with anelevator-shaft and to retard its downward movement by the [o and a car,cab, or platform Working therein, liquid in the cylinder, the Wholeforming a of a liquid-cylinder at the bottom of said safety applianceindependent of the mechanshaft, a valvular piston or plunger looselyfitism employed to operate the car, cab, or plat- 5 ting said cylinderand attached to and movform, substantially as herein described.

ing with said car or cab, and a valve applied ROBT. A. GHESEBBOUGH.

to said piston or plunger and serving to per- Vitnesses: wit a freeupward passage of the piston or 'J. F. VVILLGOX, plunger through theliquid in the cylinder, S. H. MCFADDEN.

